Volumetric Expansion Calculator

Enter γ, the starting volume, and the temperature rise. You get how much the volume grows. At 3.6e-5, 1 m³ and 50 K you get 0.0018 m³. For steel that is roughly 3α.

Linear: Δl = α·l₀·ΔT. Heat at the same ΔT: Q = c·m·ΔT.

Inputs

Result

γ (1/K), Volume V₀ (m³, SI) and ΔT (K). The result shows up here.

How it works

V₀ ΔV = γ·V₀·ΔT dla ciał stałych γ ≈ 3α
Volume grows with temperature: ΔV = γ·V₀·ΔT. For solids γ ≈ 3α.

Volume grows with temperature: ΔV = γ·V₀·ΔT. Final V = V₀ + ΔV. The calculator example: γ = 0.000036, V₀ = 1 m³, ΔT = 50 gives ΔV = 0.0018 m³. That is 1.8 liters per cubic meter, small on that scale, visible on a tank.

For solids γ ≈ 3α, because three dimensions grow. Steel α = 12e-6 gives γ ≈ 36e-6. If you know α from the linear page, you can estimate γ and come back here. Liquids have their own γ from a table, not 3α of steel. Water near 20 °C is on the order of 2e-4 1/K.

Keep V₀ in cubic meters. One liter is 0.001 m³. If you type 1 thinking of a liter, ΔV comes out a thousand times too large. γ is in 1/K. ΔT is again a difference: 20 K, not 293.

At V₀ = 0.001 m³, γ = 3.6e-5 and ΔT = 20 K you get ΔV = 7.2e-7 m³, about 0.72 ml. With the same data and 50 K it is 1.8 ml. A negative ΔT means contraction.

This formula does not give heat. Energy for the same temperature jump is Q = c m ΔT. Here you only get volume geometry.

Type γ, V₀ and ΔT, then Calculate. 0.000036, 1 and 50 should come back as 0.0018 m³. A comma in 0.000036 parses the same as a period.

How to use

  1. Type γ. For steel about 0.000036, that is 3.6e-5, roughly 3α.
  2. Type V₀ in m³. One liter is 0.001, not 1.
  3. Type ΔT as a rise in kelvin, for example 50. Do not add 273.
  4. Click Calculate. 0.000036, 1 m³ and 50 K give 0.0018 m³.
  5. For α in one dimension, open linear expansion. For energy, open Q = c m ΔT.

Formula

ΔV = γ · V0 · ΔT

For solids γ ≈ 3α. V₀ in m3.

Letters in ΔV = γ·V₀·ΔT

Volume grows as ΔV = γ·V₀·ΔT. At γ = 3.6×10⁻⁵, 1 m³ and 50 K you get 0.0018 m³, 1.8 liters per cubic meter.

ΔV
Volume increase in m³. 0.000036 × 1 × 50 = 0.0018 m³ on the page example.
γ
Volume coefficient in 1/K. For steel about 3.6×10⁻⁵, roughly 3α from 12×10⁻⁶.
V₀
Starting volume in m³. A one is a cubic meter; type a liter as 0.001, or ΔV is a thousand times too large.
ΔT
Rise in kelvin, the same 50 K as on the bar, except here the volume swells, not the length.

Real-life examples

Example 1

ΔV = 1.8×10⁻³ m³.

Example 2

α = 1.2×10⁻⁵ → γ ≈ 3.6×10⁻⁵, V₀ = 1, ΔT = 50.

Example 3

V₀ = 0.001, γ = 3.6×10⁻⁵, ΔT = 50.

Example 4

V₀ = 1, ΔT = 40.

Example 5

V₀ = 0.5, ΔT = 80.

Example 6

V₀ = 2, γ = 3.6×10⁻⁵, ΔT = 30.

Example 7

V₀ = 1, ΔT = −25.

Example 8

V₀ = 0.0001, ΔT = 100.

Example 9

γ = 2×10⁻⁴, V₀ = 0.001, ΔT = 20.

Example 10

V₀ = 10, γ = 3.6×10⁻⁵, ΔT = 20.

Ways to use this calculator

  • From steel α = 12e-6 you make γ ≈ 36e-6 and compute the rise of a cubic meter.
  • You convert a liter to 0.001 m³ so ΔV is not a thousand times too large.

Frequently asked questions

How much ΔV at γ = 3.6e-5, V₀ = 1 m³ and ΔT = 50 K?

ΔV = 0.0018 m³. Final V = 1.0018 m³ after that 50 K rise.

How much at V₀ = 0.001 m³, γ = 3.6e-5 and ΔT = 20 K?

ΔV = 7.2e-7 m³, about 0.72 ml. At 50 K it is 1.8 ml.

Why is γ ≈ 3α at α = 12e-6?

Three dimensions. 3 × 12e-6 = 36e-6 1/K. Liquids have their own γ, not 3α of steel.

Is 1 in the V₀ field a liter?

No. The calculator needs m³. Type a liter as 0.001. A one is already a full cubic meter.

Can ΔT be negative?

Yes. Then ΔV is negative: the volume shrinks on cooling.

What γ does water have near 20 °C?

On the order of 2e-4 1/K, not 3α of steel. Take the constant from a liquid table.

Does this formula compute joules?

No. Heat for that ΔT lives on Q = c m ΔT. Here only ΔV.

Where do I compute a bar growing longer?

On linear expansion, Δl = α l₀ ΔT. From there you take α into 3α.

Does 3.6e-5 work?

Yes. 3.6e-5, 3.6×10⁻⁵ and 0.000036 are the same γ.

What unit is the result?

Cubic meters. 0.0018 m³ is 1.8 liters. The calculator does not convert V₀ to gallons inside the formula.

Knowledge sources

The formula is the school one. Units follow SI; NIST SP 330 and BIPM define the measures, not your result.

Page updated in 2026.